A sentinel is a loop exit value or list delimiter whose value is outside the range of valid input, such as -1 for a zero-based array index, or ~ for alphabetic strings.
Questions tagged [sentinel]
410 questions
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Issues Querying and Downloading Sentinel-3 OLCI Data with Sentinelsat
I am working with Sentinel-3 OLCI Level-2 Data Products with the Sentinelsat API and am having issues querying and exceeding my data download quota. Overall, I would like to write a program that accepts a date range and a specific geographic…
Tyler Dejong
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How to use sentinel to know you have gone offline?
I have a redis sentinel cluster configured with 5 nodes with the following IPs:
192.168.1.1
192.168.1.2
192.168.1.3
192.168.1.4
192.168.1.5
I wish to find a simple way to determine if any server has gone offline from its own point of view.
On…
Harry Boy
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Is sentinel node exactly dummy node?
Let us say in a linked list, many leetcode solutions suggest that we can create a dummy node to make a problem easier ( dummy_node = ListNode(0) ). My DS&A professor also recommends us to have a sentinel node pointing to the head of the linked list.…
BattleWoLFz99
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Mapview: edit map - Raster image too large; 19177520 bytes is greater than maximum 4194304 bytes
I was trying to create a supervised classification with Sentinel image via R but the mapview function cannot show the map because the raster image is said to be large. I already set the default to InF (infinite) but still shows the same error. Is…
Johnny
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2 answers
How to set password for redis-server
I have a 3-instance high availability redis deployed. On each server I have redis and sentinel installed. I am trying to set a password
so that it requests it at the moment of entering with the command "redis-cli".
I am modifying the value of the…
user14867757
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1 answer
How to write this sentinel loop having a null check in a cleaner, shorter and efficient way?
I am using null as a sentinel/trip value to break out of foreach:
public static DataTable ExecuteQuery(string sql)
{
var conn = new SqlConnection(EnvironmentVariables.GetDbConnectionString());
var adapter = new SqlDataAdapter(sql, conn);
…
k_rollo
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Unable to access and download Sentinel-2 images from Python API with the standard code
rec = POLYGON ((597843.23 2977645.792070312, 686175.1025585937 2977645.792070312, 686175.1025585937 3112308.537736816, 597843.23 3112308.537736816, 597843.23 2977645.792070312))
products = api.query(rec,
date = ('20191001',…
Inshu Chauhan
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GEE supervised classification from Sentinel-2 with shapefiles
I am a beginner in GEE and I have a problem with making supervised classification from Sentinel-2 data. I used my pre-made shapefiles in five categories as training data. I tried more codes but the classification doesn't work. I don't know if it is…
Anna Brandejsová
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Redis HA with Sentinel on Docker
I'm struggling now for a week with the Redis HA on Docker. I am not quite convinced if my intentions will even works. The documentation is understandable, but there are many examples which do not correspond to the documentation.
Well, what I want to…
ETfraXoR
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Kusto Search across Sentinel workspaces from a watchlist
At the moment the way I search SecurityEvent across all workspaces is to create a function that contains the following search syntax:
union
workspace("workspaceid1").SecurityEvent, workspace("workspaceid2").SecurityEvent,…
Jaysec
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2 answers
Swapping neighbor linked list nodes
I have to make a function which swaps the neighbor nodes in a linked list with sentinel. Something like this: 1-2-3-4-5 -> 2-1-4-3-5, but I don't know how to do that. Can somebody help me?
#include
#include
typedef struct…
Csaba Bársics
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Redis Sentinel - How the new master is chosen?
I'm trying to set up Redis Sentinel.
I know that when a master goes down the sentinel pick up one of its slaves and promote it as master.
I was wondering based on which attributes the new master is selected among the slaves and which slave got…
zahra.dgh
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Failed to connect to sentinel from java app on local machine
Trying to prepare docker-compose file for local development which will be similar to prod setup as much as possible.
Here is my docker-compose.yml:
version: '3'
services:
redis-master:
image: redis:6.0.5
redis-slave:
image: redis:6.0.5
…
AlmostVoidCrusade
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What is the point of "sentinel object" pattern in Python
I recently learned about the "sentinel object" pattern in python. I was taken by it, and started to use it wherever I could. However, after using it someplace where it isn't needed, a coworker asked me about it. Now, I can't see the use of it, given…
hhoke1
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Why Would you use None as a Sentinel in a Function in Python?
version 1
def add_author(authors_books, current_books=None):
if current_books is None:
current_books = []
current_books.extend(authors_books)
return current_books
version 2
def add_author(authors_books):
current_books = []
…
Gojilla
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